Biotechnology for Biofuels最新文献

{"title":"Biochemical and inhibitor analysis of recombinant cellobiohydrolases from Phanerochaete chrysosporium","authors":"Bianca Oliva,&nbsp;André Ferraz,&nbsp;Fernando Segato","doi":"10.1186/s13068-024-02584-4","DOIUrl":"10.1186/s13068-024-02584-4","url":null,"abstract":"<div><p>The demand for greener energy sources necessitates the development of more efficient processes. Lignocellulosic biomass holds significant potential for biofuels production, but improvements in its enzymatic degradation are required to mitigate the susceptibility of enzymes by reaction products and pretreatment impurities. In this work, two cellobiohydrolases (CBHs) from the basidiomycete <i>Phanerochaete chrysosporium</i> (<i>Pc</i>Cel7C and <i>Pc</i>Cel7D) were heterologously expressed, characterized, and analyzed in the presence of their products (glucose and cellobiose) and harmful compounds commonly found in industrial processes (phenolics), as well as their adsorption to lignin and cellulose. The enzymes exhibited an optimum temperature of 55 °C and displayed a pH profile similar to the model CBHI from <i>Trichoderma reesei</i> (<i>Tr</i>Cel7A). Activity decreased consistently for all CBHs in the presence of cellobiose, while glucose significantly impacted the basidiomycete CBHs. Phenolic compounds with a higher content of OH groups were found to be more detrimental to the enzymes, with the location of the OH group on the phenolic ring playing a crucial role in enzyme deactivation. Molecular docking simulations predicted that the product-binding site of CBHs has the highest affinity for interaction with phenolics; however, they are unlikely to interact at this site in the presence of substrate. <i>Pc</i>Cel7C and <i>Pc</i>Cel7D exhibited poorer adsorption on cellulose compared to the <i>Tr</i>Cel7A enzyme. These findings provide insights into how the structure of CBHs influences their susceptibility to inhibitors and deactivating compounds present in saccharification reaction medium.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02584-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142754286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat of reaction in individual metabolic pathways of yeast determined by mechanistic modeling in an insulated bioreactor","authors":"Yusmel González-Hernández,&nbsp;Emilie Michiels,&nbsp;Patrick Perré","doi":"10.1186/s13068-024-02580-8","DOIUrl":"10.1186/s13068-024-02580-8","url":null,"abstract":"<div><h3>Background</h3><p>The yeast <i>Saccharomyces cerevisiae</i>, commonly used in industry, exhibits complex metabolism due to the Crabtree effect, fermenting alcohol even under aerobic conditions when glucose exceeds 0.10-0.15 g/L. The heat released by the biological activity is a signal very easy to collect, given the minimal instrumentation requirements. However, this heat depends on the activated metabolic pathways and provides only an indirect indicator, that cannot be used in a simple way. This study demonstrated the potential of a mechanistic model to control the process by measuring the heat released by the biological activity.</p><h3>Results</h3><p>The complexity arising from coexisting metabolic pathways was addressed by a comprehensive model of <i>Saccharomyces cerevisiae</i> together with the heat of reaction included in a rigorous enthalpy balance of the bioreactor. Batch cultures were performed in an insulated bioreactor to trigger a temperature signal. The heat of individual metabolic pathways was determined by inverse analysis of these tests using Particle Swarm Optimization (PSO): -101.28 ±0.02kJ/mol for anaerobic fermentation, -231.27±0.06kJ/mol for aerobic fermentation, and -662.94 ± 0.54kJ/mol for ethanol respiration. Finally, the model was successfully applied and validated for online training under different operating conditions.</p><h3>Conclusions</h3><p>The model demonstrates remarkable accuracy, with a mean relative error under 0.38% in temperature predictions for both anaerobic and aerobic conditions. The viscous dissipation is a key parameter specific to the bioreactor and the growth conditions. However, we demonstrated that this parameter could be fitted accurately from the early stages of the experiment for further prediction of the remaining part. This model introduces temperature, or the thermal power required to maintain temperature, as a measurable parameter for online feedback model training to provide increasingly precise feed-forward control.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02580-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142694854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sequential pretreatment with hydroxyl radical and manganese peroxidase for the efficient enzymatic saccharification of corn stover","authors":"Man Zhou,&nbsp;Yaru Wang,&nbsp;Yuan Wang,&nbsp;Tao Tu,&nbsp;Jie Zhang,&nbsp;Xiaolu Wang,&nbsp;Guijie Zhang,&nbsp;Huoqing Huang,&nbsp;Bin Yao,&nbsp;Huiying Luo,&nbsp;Xing Qin","doi":"10.1186/s13068-024-02583-5","DOIUrl":"10.1186/s13068-024-02583-5","url":null,"abstract":"<div><h3>Background</h3><p>White rot fungi produce various reactive oxygen species and ligninolytic enzymes for lignocellulose deconstruction. However, their interactions during the deconstruction of lignocellulosic structural barriers for efficient enzymatic saccharification remain unclear.</p><h3>Results</h3><p>Herein, the extracellular enzyme activities and secretomic analysis revealed the sequential expression of hydroxyl radical (⋅OH) and manganese peroxidases (MnPs) for lignocellulose deconstruction by the white rot fungus <i>Irpex lacteus</i>. Subsequently, in vitro functional studies found that ⋅OH possessed the ability to disrupt the smooth surface structure of corn stover, resulting in increased enzymatic saccharification and cellulose accessibility. Purified recombinant MnPs from <i>I. lacteus</i> were able to cleave the β-<i>O</i>-4 bond in phenolic and non-phenolic lignin model dimers without the help of any mediators. Furthermore, the sequential pretreatment of corn stover with ⋅OH and MnP exhibited significant synergistic effects, increasing enzymatic saccharification and cellulose accessibility by 2.9-fold and 1.8-fold, respectively.</p><h3>Conclusions</h3><p>These results proved for the first time the synergistic effects of ⋅OH and MnP pretreatment in improving the enzymatic saccharification and cellulose accessibility of corn stover. These findings also demonstrated the potential application of ⋅OH and MnP pretreatment for the efficient enzymatic saccharification of corn stover.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02583-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of non-oleaginous green microalgae Ulothrix for bio-fixing CO2 and producing biofuels by ARTP mutagenesis","authors":"Mingshan Yin,&nbsp;Yuliang An,&nbsp;Feng Qi,&nbsp;Ruimin Mu,&nbsp;Guixia Ma,&nbsp;Feiyong Chen","doi":"10.1186/s13068-024-02577-3","DOIUrl":"10.1186/s13068-024-02577-3","url":null,"abstract":"<div><p>Oleaginous green microalgae are often mentioned in algae-based biodiesel industry, but most of them belong to specific genus (<i>Chlorella</i>, <i>Scenedesmus</i>, <i>Botryococcus</i> and <i>Desmodesmus</i>). Thus, the microalgal germplasm resources for biodiesel production are limited. Mutagenesis is regarded as an important technology for expanding germplasm resources. The main purpose of this study is to screen microalgae strains with high carbon dioxide tolerance and high lipid content from mutants derived from indigenous non-oleaginous green microalgae species—<i>Ulothrix</i> SDJZ-17. Two mutants with high CO₂ tolerance and high lipid content genetic stability were obtained from the mutants by high-throughput screening, named <i>Ulothrix</i> SDJZ-17-A20 and <i>Ulothri</i>x SDJZ-17-A23. In order to evaluate the potential of CO₂ fixation and biofuel production, A20 and A23 were cultured under air and 15% CO₂ (v/v) conditions, and their wild-type strains (WT) were used as controls. Under the condition of high CO₂ concentration, the growth performance and lipid production capacity of mutant strains A20 and A23 were not only significantly better than those of wild strains, but also better than those of their own cultured under air conditions. Among them, A23 obtained the highest LCE (light conversion efficiency) (14.79%), <i>Fv/Fm </i>(maximal photochemical efficiency of photosystem II) (71.04%) and biomass productivity (81.26 mg L⁻¹ d⁻¹), while A20 obtained the highest lipid content (22.45%). Both mutants can be used as candidate strains for CO₂ fixation and biofuel production. By ARTP (atmospheric and room temperature plasma) mutagenesis with high-throughput screening, the mutants with higher CO₂ tolerance, photosynthetic efficiency and lipid productivity can be obtained, even if they are derived from non-oleaginous microalgae, which is of great significance for enriching the energy microalgae germplasm bank, alleviating the global warming and energy crisis.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02577-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142634232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential, economic and ecological benefits of sweet sorghum bio-industry in China","authors":"Ru Zhang,&nbsp;Gang Lin,&nbsp;Li Shang,&nbsp;Xiaoyuan Wu,&nbsp;Zhiquan Liu,&nbsp;Longchao Xu,&nbsp;Qinglin Sun,&nbsp;Jingying Fu,&nbsp;Huaiqing Hao,&nbsp;Hai-Chun Jing","doi":"10.1186/s13068-024-02582-6","DOIUrl":"10.1186/s13068-024-02582-6","url":null,"abstract":"<div><h3>Background</h3><p>Sweet sorghum (<i>Sorghum bicolor</i>) displays an excellent potential to serve as a non-food bioenergy feedstock for bioethanol production in China due to its high potential yield on marginal lands. However, few studies have been conducted on the potential of sweet sorghum yield and appropriate industrial models in different marginal regions in China. This study explored the spatial distribution of potential sweet sorghum production using the Decision Support System for Agrotechnology Transfer (DSSAT) model and proposed three typical industrial models of sweet sorghum industry to calculate their economic and ecological benefits.</p><h3>Results</h3><p>The results indicate that considering the factors of land use, annual precipitation, soil salinity, soil pH, and accumulated temperature, approximately 32.23 million ha of marginal land are suitable for sweet sorghum cultivation in China, and 130 million tonnes (t) of ethanol can be produced. Further, the development of the sweet sorghum industry under the three models can generate 1425.49 billion CNY potential, approximately accounting for 3.57% of industrial added value in China if measured against 2023 levels, and reduce CO₂ emissions by 4.68 million t.</p><h3>Conclusions</h3><p>This study provides an innovative perspective for the multi-industry large-scale promotion of sweet sorghum in different marginal lands based on the high spatial resolution Geographic Information System (GIS) data by the DSSAT model with a Life Cycle Assessment (LCA) method, and this applies not only to China but also to the worldwide and other types of energy plants.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02582-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142595298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production and characterization of novel/chimeric sophorose–rhamnose biosurfactants by introducing heterologous rhamnosyltransferase genes into Starmerella bombicola","authors":"Mingxin Liu,&nbsp;Tianshuang Tu,&nbsp;Hui Li,&nbsp;Xin Song","doi":"10.1186/s13068-024-02581-7","DOIUrl":"10.1186/s13068-024-02581-7","url":null,"abstract":"<div><p>Glycolipid biosurfactant, sophorolipids (SLs) and rhamnolipids (RLs) can be widely used in agriculture, food and chemical industries. The different physicochemical properties of SLs and RLs, such as hydrophilic lipophilic value (HLB) and critical micelle concentration (CMC), determine they have different application focus. Researchers are still hoping to obtain new glycolipid surfactants with unique surface activities. In this study, we successfully transformed two rhamnosyltransferase genes <i>rhlA</i> and <i>rhlB</i> from <i>Pseudomonas aeruginosa</i> to the sophorolipid-producing <i>Starmerella bombicola</i> CGMGG 1576 to obtain a recombinant strain was <i>Sb</i>_<i>rhlAB</i>. Two novel components with molecular weight of 554 (C₂₆H₅₀O₁₂) and 536 (C₂₆H₄₈O₁₁) were identified with the ASB C₁₈ column from the fermentation broth of <i>Sb</i>_<i>rhlAB</i>, the former was a non-acetylated acidic C14:0 glycolipid containing one glucose and one rhamnose, and the latter was an acidic C14:1 glycolipid containing two rhamnoses. With the Venusil MP C₁₈ column, one new glycolipid component was identified as an acidic C18:3 glycolipid with one rhamnose (C₂₄H₄₀O₇), which has not been reported before. Our present study demonstrated that novel glycolipids can be synthesized in vivo by reasonable genetic engineering. The results will be helpful to engineer sophorolipid-producing yeast to produce some specific SLs or their derivatives in more rational and controllable way.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02581-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142585205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous saccharification and fermentation for d-lactic acid production using a metabolically engineered Escherichia coli adapted to high temperature","authors":"Gilberto Pérez-Morales,&nbsp;Luis Caspeta,&nbsp;Enrique Merino,&nbsp;Miguel A. Cevallos,&nbsp;Guillermo Gosset,&nbsp;Alfredo Martinez","doi":"10.1186/s13068-024-02579-1","DOIUrl":"10.1186/s13068-024-02579-1","url":null,"abstract":"<div><h3>Background</h3><p><i>Escherichia coli</i> JU15 is a metabolically engineered strain capable to metabolize C5 and C6 sugars with a high yield of <span>d</span>-lactic acid production at its optimal growth temperature (37 °C). The simultaneous saccharification and fermentation process allow to use lignocellulosic biomass as a cost-effective and high-yield strategy. However, this process requires microorganisms capable of growth at a temperature close to 50 °C, at which the activity of cellulolytic enzymes works efficiently.</p><h3>Results</h3><p>The thermotolerant strain GT48 was generated by adaptive laboratory evolution in batch and chemostat cultures under temperature increments until 48 °C. The strain GT48 was able to grow and ferment glucose to<span> d</span>-lactate at 47 °C. It was found that a pH of 6.3 conciliated with GT48 growth and cellulase activity of a commercial cocktail. Hence, this pH was used for the SSF of a diluted acid-pretreated corn stover (DAPCS) at a solid load of 15% (<i>w</i>/<i>w</i>), 15 FPU/g-_DAPCS, and 47 °C. Under such conditions, the strain GT48 exhibited remarkable performance, producing <span>d</span>-lactate at a level of 1.41, 1.42, and 1.48-fold higher in titer, productivity, and yield, respectively, compared to parental strain at 45 °C.</p><h3>Conclusions</h3><p>In general, our results show for the first time that a thermal-adapted strain of <i>E. coli</i> is capable of being used in the simultaneous saccharification and fermentation process without pre-saccharification stage at high temperatures.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02579-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142565295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expanding the biosynthesis spectrum of hydroxy fatty acids: unleashing the potential of novel bacterial fatty acid hydratases","authors":"Yu Chyuan Heng,&nbsp;Garrett Wei Jie Wong,&nbsp;Sandra Kittelmann","doi":"10.1186/s13068-024-02578-2","DOIUrl":"10.1186/s13068-024-02578-2","url":null,"abstract":"<div><h3>Background</h3><p>Hydroxy fatty acids represent an emerging class of compounds with promising applications in the chemical, medicinal and functional food sectors. The challenges associated with their chemical synthesis have spurred exploration of biological synthesis as an alternative route, particularly through the use of fatty acid hydratases. Fatty acid hydratases catalyse the regioselective addition of a hydrogen atom and a hydroxyl group from a water molecule to the carbon–carbon <i>cis</i>-double bond of unsaturated fatty acids to form hydroxy fatty acids. Despite having been discovered in the early 1960s, previous research has primarily focused on characterizing single fatty acid hydratase variants with a limited range of substrates. Comprehensive studies that systematically examine and compare the characteristics of multiple variants of fatty acid hydratases are still lacking.</p><h3>Results</h3><p>In this study, we employed an integrated bioinformatics workflow to identify 23 fatty acid hydratases and characterized their activities against nine unsaturated fatty acid substrates using whole-cell biotransformation assays. Additionally, we tested a dual-protein system involving two fatty acid hydratases of distinct regioselectivity and demonstrated its suitability in enhancing the biosynthesis of di-hydroxy fatty acids.</p><h3>Conclusions</h3><p>Our study demonstrates that fatty acid hydratases can be classified into three subtypes based on their regioselectivity and provides insights into their preferred substrate structures. These understandings pave ways for the design of optimal fatty acid hydratase variants and bioprocesses for the cost-efficient biosynthesis of hydroxy fatty acids.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02578-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142514612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering the L-tryptophan metabolism for efficient de novo biosynthesis of tryptophol in Saccharomyces cerevisiae","authors":"Ye Li,&nbsp;Jingzhen Sun,&nbsp;Zhenhao Fu,&nbsp;Yubing He,&nbsp;Xiaorui Chen,&nbsp;Shijie Wang,&nbsp;Lele Zhang,&nbsp;Jiansheng Jian,&nbsp;Weihua Yang,&nbsp;Chunli Liu,&nbsp;Xiuxia Liu,&nbsp;Yankun Yang,&nbsp;Zhonghu Bai","doi":"10.1186/s13068-024-02576-4","DOIUrl":"10.1186/s13068-024-02576-4","url":null,"abstract":"<div><p>Tryptophol (IET) is a metabolite derived from L-tryptophan that can be isolated from plants, bacteria, and fungi and has a wide range of biological activities in living systems. Despite the fact that IET biosynthesis pathways exist naturally in living organisms, industrial-scale production of IET and its derivatives is solely based on environmentally unfriendly chemical conversion. With diminishing petroleum reserves and a significant increase in global demand in all major commercial segments, it becomes essential to develop new technologies to produce chemicals from renewable resources and under mild conditions, such as microbial fermentation. Here we characterized and engineered the less-studied L-tryptophan pathway and IET biosynthesis in the baker’s yeast <i>Saccharomyces cerevisiae</i>, with the goal of investigating microbial fermentation as an alternative/green strategy to produce IET. In detail, we divided the aromatic amino acids (AAAs) metabolism related to IET synthesis into the shikimate pathway, the L-tryptophan pathway, the competing L-tyrosine/L-phenylalanine pathways, and the Ehrlich pathway based on a modular engineering concept. Through stepwise engineering of these modules, we obtained a yeast mutant capable of producing IET up to 1.04 g/L through fed-batch fermentation, a ~ 650-fold improvement over the wild-type strain. Besides, our engineering process also revealed many insights about the regulation of AAAs metabolism in <i>S. cerevisiae</i>. Finally, during our engineering process, we also discovered yeast mutants that accumulate anthranilate and L-tryptophan, both of which are precursors of various valuable secondary metabolites from fungi and plants. These strains could be developed to the chassis for natural product biosynthesis upon introducing heterologous pathways.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02576-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineered reduction of S-adenosylmethionine alters lignin in sorghum","authors":"Yang Tian,&nbsp;Yu Gao,&nbsp;Halbay Turumtay,&nbsp;Emine Akyuz Turumtay,&nbsp;Yen Ning Chai,&nbsp;Hemant Choudhary,&nbsp;Joon-Hyun Park,&nbsp;Chuan-Yin Wu,&nbsp;Christopher M. De Ben,&nbsp;Jutta Dalton,&nbsp;Katherine B. Louie,&nbsp;Thomas Harwood,&nbsp;Dylan Chin,&nbsp;Khanh M. Vuu,&nbsp;Benjamin P. Bowen,&nbsp;Patrick M. Shih,&nbsp;Edward E. K. Baidoo,&nbsp;Trent R. Northen,&nbsp;Blake A. Simmons,&nbsp;Robert Hutmacher,&nbsp;Jackie Atim,&nbsp;Daniel H. Putnam,&nbsp;Corinne D. Scown,&nbsp;Jenny C. Mortimer,&nbsp;Henrik V. Scheller,&nbsp;Aymerick Eudes","doi":"10.1186/s13068-024-02572-8","DOIUrl":"10.1186/s13068-024-02572-8","url":null,"abstract":"<div><h3>Background</h3><p>Lignin is an aromatic polymer deposited in secondary cell walls of higher plants to provide strength, rigidity, and hydrophobicity to vascular tissues. Due to its interconnections with cell wall polysaccharides, lignin plays important roles during plant growth and defense, but also has a negative impact on industrial processes aimed at obtaining monosaccharides from plant biomass. Engineering lignin offers a solution to this issue. For example, previous work showed that heterologous expression of a coliphage <i>S</i>-adenosylmethionine hydrolase (AdoMetase) was an effective approach to reduce lignin in the model plant Arabidopsis. The efficacy of this engineering strategy remains to be evaluated in bioenergy crops.</p><h3>Results</h3><p>We studied the impact of expressing AdoMetase on lignin synthesis in sorghum (<i>Sorghum bicolor</i> L. Moench). Lignin content, monomer composition, and size, as well as biomass saccharification efficiency were determined in transgenic sorghum lines. The transcriptome and metabolome were analyzed in stems at three developmental stages. Plant growth and biomass composition was further evaluated under field conditions. Results evidenced that lignin was reduced by 18% in the best transgenic line, presumably due to reduced activity of the <i>S</i>-adenosylmethionine-dependent <i>O</i>-methyltransferases involved in lignin synthesis. The modified sorghum features altered lignin monomer composition and increased lignin molecular weights. The degree of methylation of glucuronic acid on xylan was reduced. These changes enabled a ~20% increase in glucose yield after biomass pretreatment and saccharification compared to wild type. RNA-seq and untargeted metabolomic analyses evidenced some pleiotropic effects associated with <i>AdoMetase</i> expression. The transgenic sorghum showed developmental delay and reduced biomass yields at harvest, especially under field growing conditions.</p><h3>Conclusions</h3><p>The expression of <i>AdoMetase</i> represents an effective lignin engineering approach in sorghum. However, considering that this strategy potentially impacts multiple <i>S</i>-adenosylmethionine-dependent methyltransferases, adequate promoters for fine-tuning <i>AdoMetase</i> expression will be needed to mitigate yield penalty.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02572-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}